Add 5/20 and 3/21
5/20 + 3/21 is 11/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
5/20 = 5 × 21/20 × 21 = 105/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
3/21 = 3 × 20/21 × 20 = 60/420 - Add the two like fractions:
105/420 + 60/420 = 105 + 60/420 = 165/420 - 165/420 simplified gives 11/28
- So, 5/20 + 3/21 = 11/28
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